Anti-peeping circuit, driving method thereof, and display device

Abstract

An anti-peeping circuit for a display panel, a driving method thereof, and a display device. The anti-peeping circuit includes a waveform generator. The waveform generator is connected to an anti-peeping electrode of the display panel, and the waveform generator is configured to generate an anti-peeping signal and output the anti-peeping signal to the anti-peeping electrode of the display panel.

What is claimed is: 
     
       1. An anti-peeping circuit for a display panel, the anti-peeping circuit comprising a waveform generator,
 wherein the waveform generator is connected to an anti-peeping electrode of the display panel, and the waveform generator is configured to generate an anti-peeping signal and output the anti-peeping signal to the anti-peeping electrode of the display panel; and 
 a calculating circuit, wherein the calculating circuit is connected to the waveform generator and the anti-peeping electrode, respectively, and the calculating circuit is configured to amplify the anti-peeping signal and output the amplified anti-peeping signal to the anti-peeping electrode, 
 
       wherein the calculating circuit comprises a first calculating sub-circuit and a second calculating sub-circuit;
 the first calculating sub-circuit comprises a first input terminal, a second input terminal and a first output terminal, 
 the second calculating sub-circuit comprises a third input terminal, a fourth input terminal and a second output terminal, 
 the first input terminal of the first calculating sub-circuit is connected to an output terminal of the waveform generator to receive the anti-peeping signal, the second input terminal of the first calculating sub-circuit is connected to a reference voltage terminal to receive a reference voltage, and the first output terminal of the first calculating sub-circuit is connected to the third input terminal of the second calculating sub-circuit; and 
 the fourth input terminal of the second calculating sub-circuit is connected to a bias voltage terminal to receive a bias voltage, and the second output terminal of the second calculating sub-circuit is connected to the anti-peeping electrode to output the amplified anti-peeping signal. 
 
     
     
       2. The anti-peeping circuit according to  claim 1 , wherein the first calculating sub-circuit is a first subtraction sub-circuit, and the second calculating sub-circuit is a second subtraction sub-circuit. 
     
     
       3. The anti-peeping circuit according to  claim 1 , wherein the waveform generator comprises a digital-to-analog converter; and
 the digital-to-analog converter is configured to perform digital-to-analog conversion on the anti-peeping signal and output the converted anti-peeping signal from an output terminal of the waveform generator. 
 
     
     
       4. The anti-peeping circuit according to  claim 1 , wherein the waveform generator further comprises an interruption unit configured to control outputting of the anti-peeping signal in a case where a trigger signal is detected, and
 the trigger signal is provided by a timing controller. 
 
     
     
       5. The anti-peeping circuit according to  claim 1 , wherein the waveform generator further comprises an input terminal, and is configured to receive an instruction for generating the anti-peeping signal. 
     
     
       6. The anti-peeping circuit according to  claim 1 , wherein each period of the anti-peeping signal comprises a gradually-changing-level region and a constant-level region. 
     
     
       7. The anti-peeping circuit according to  claim 1 , wherein the bias voltage is configured so that a first difference value of the anti-peeping signal is equal to a second difference value of the anti-peeping signal; and
 the first difference value is a difference value between a first level of the anti-peeping signal and a common voltage, and the second difference value is a difference value between a second level of the anti-peeping signal and the common voltage. 
 
     
     
       8. The anti-peeping circuit according to  claim 7 , wherein the first calculating sub-circuit is a first subtraction sub-circuit, and the second calculating sub-circuit is a second subtraction sub-circuit. 
     
     
       9. The anti-peeping circuit according to  claim 7 , wherein the waveform generator comprises a digital-to-analog converter; and
 the digital-to-analog converter is configured to perform digital-to-analog conversion on the anti-peeping signal and output the converted anti-peeping signal from the output terminal of the waveform generator. 
 
     
     
       10. A display device, comprising the anti-peeping circuit according to  claim 1  and a display panel,
 wherein the display panel comprises an anti-peeping electrode, and the anti-peeping electrode is electrically connected to the anti-peeping circuit. 
 
     
     
       11. The display device according to  claim 10 , wherein the display panel is a liquid crystal display panel, and
 the anti-peeping electrode is at a displaying side of the liquid crystal display panel and covers at least a display area. 
 
     
     
       12. The display device according to  claim 11 , wherein the liquid crystal display panel comprises: a first substrate, a second substrate opposite to the first substrate, and a liquid crystal layer between the first substrate and the second substrate; and
 the anti-peeping electrode is on the second substrate, and is configured to apply an electrical signal to the liquid crystal layer under a control of the anti-peeping signal output by the anti-peeping circuit. 
 
     
     
       13. The display device according to  claim 10 , further comprising a timing controller, wherein the timing controller is configured to be connected to the anti-peeping circuit and a gate driving circuit of the display panel to provide a trigger signal. 
     
     
       14. A driving method of an anti-peeping circuit for a display panel, the anti-peeping circuit comprising a waveform generator, wherein the waveform generator is connected to an anti-peeping electrode of the display panel, and the waveform generator is configured to generate an anti-peeping signal and output the anti-peeping signal to the anti-peeping electrode of the display panel, and
 the driving method comprises: 
 generating the anti-peeping signal by the waveform generator, and inputting the anti-peeping signal to the anti-peeping electrode of the display panel, and 
 the anti-peeping circuit further comprises a calculating circuit, and the driving method further comprises: amplifying, by the calculating circuit, the anti-peeping signal generated by the waveform generator; and sending the amplified anti-peeping signal to the anti-peeping electrode of the display panel, 
 wherein the calculating circuit comprises a first calculating sub-circuit and a second calculating sub-circuit,
 the first calculating sub-circuit comprises a first input terminal, a second input terminal and a first output terminal, 
 the second calculating sub-circuit comprises a third input terminal, a fourth input terminal and a second output terminal, 
 the first input terminal of the first calculating sub-circuit is connected to an output terminal of the waveform generator to receive the anti-peeping signal, the second input terminal of the first calculating sub-circuit is connected to a reference voltage terminal to receive a reference voltage, and the first output terminal of the first calculating sub-circuit is connected to the third input terminal of the second calculating sub-circuit; and 
 the fourth input terminal of the second calculating sub-circuit is connected to a bias voltage terminal to receive a bias voltage, and the second output terminal of the second calculating sub-circuit is connected to the anti-peeping electrode to output the amplified anti-peeping signal. 
 
 
     
     
       15. The driving method according to  claim 14 , wherein the waveform generator comprises an interruption unit, and the driving method further comprises:
 outputting by the waveform generator the anti-peeping signal to the anti-peeping electrode, in a case where the interruption unit detects a trigger signal.